51137388 has 18 divisors (see below), whose sum is σ = 129264044. Its totient is φ = 17045784.

The previous prime is 51137369. The next prime is 51137399. The reversal of 51137388 is 88373115.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 1420483 = 51137388 / (5 + 1 + 1 + 3 + 7 + 3 + 8 + 8).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 710206 + ... + 710277.

Almost surely, 2^51137388 is an apocalyptic number.

It is an amenable number.

51137388 is an abundant number, since it is smaller than the sum of its proper divisors (78126656).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51137388 is a wasteful number, since it uses less digits than its factorization.

51137388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1420493 (or 1420488 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 51137388 is about 7151.0410430930. The cubic root of 51137388 is about 371.1756808006.

The spelling of 51137388 in words is "fifty-one million, one hundred thirty-seven thousand, three hundred eighty-eight".